[aprssig] Re: PHG in APRS and Xastir?

[Curt, WE7U]

On Thu, 11 May 2006, Robert Bruninga wrote:

> I was surprised to see an Xastir station without any
> PHG data.  I thought UIview was the only software
> that omitted this fundamental dimension to APRS?

Xastir has it, but also has a "Disable PHG" button in the same
dialog.


> This is a royal pain for something that was supposed to
> be fundamentally included in APRS all the time.

Chapter 7 of the spec, "APRS DATA EXTENSIONS", says this:

  "A fixed-length 7-byte field may follow APRS position data.  This
   field is an APRS Data Extension.  The extension may be one of the
   following:
   ...
   PHGphgd Station Power and Effective Antenna Height/Gain/Directivity"

I read that to say that PHG is an optional field, which is one
reason there's a DISABLE togglebutton on the dialog.  The other main
reason is to keep packets very short, giving a higher success rate.


> Can
> the Xastir authors consider making users enter their PHG
> data at the same time they do their initial set up of callsign,
> lat and long?

That's exactly the dialog that the PHG stuff is on.  The users have
a choice whether they want to set it up or disable it.

Just ask that particular user to enable/configure PHG.


> To see the evolving Omni-DF solution, see:
>
> http://www.ew.usna.edu/~bruninga/dfing.html

That's cool, and good practice.  Good luck finding the station!

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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